/**
 * Verifies a JWT token
 *
 * @function
 * @param {string} jwt - The JSON Web Token to verify.
 * @param {string | Buffer} privateKey - The private key used to verify the JWT
 *  signature.
 * @return {boolean} Returns true if the JWT signature is verified successfully,
 *  otherwise returns false.
 * @throws {MissingPrivateKeyError} Throws an error if the private key is
 *  missing.
 * @throws {InvalidPrivateKeyError} Throws an error if the private key is not
 *  a string or buffer.
 *
 * @example
 * Validate a JWT token
 *
 * ```js
 * const privateKey = fs.readFileSync('./private.key');
 * if (verifySignature(token, privateKey)) {
 *   console.log('JWT signature verified.');
 * } else {
 *   console.log('JWT signature verification failed.');
 * }
 * ```
 */
declare const verifySignature: (jwt: string, privateKey: string | Buffer) => boolean;

export { verifySignature };